Feces expelled from animals including humans are very useful for an occult blood test, i.e., for the diagnosis of various diseases such as tumors of lower gastrointestinal tracts including large intestine and therefore are used widely as a clinical test sample. For the above diagnosis, a constant amount of feces should be collected and then buffered with a proper liquid. In order to achieve this requirement by using a simple, hygienic, and accurate means and realize hygienic storage and transport of collected feces, various feces sampling containers have been developed and reported (see, for example, patent documents 1 to 8).
However, the above feces sampling containers have sometimes difficulty in adjusting the sampling amount of feces upon quantitative test, depending on the characteristic and appearance of feces to be tested because feces differ in characteristic and appearance, and in addition to normal feces, there are, for example, high fiber feces and watery feces. Further, due to a difference in the characteristic and appearance, etc. of the feces to be tested, the sampling amount varies greatly among feces samples.
In various clinical tests using feces samples, particularly a test for an antigen contained in the feces samples by utilizing an antigen-antibody reaction, a predetermined sampling amount is required to be secured irrespective of the characteristic and appearance of the feces to be tested. At the same time, the concentration of feces in a feces sample buffer should be a constant level, but it is difficult to carry out a quantitative test by using the above feces sampling containers.
Moreover, there has not been a full investigation of a feces sampling container permitting hygienic and easy confirmation, from the outside of the container, of whether or not the feces have been collected upon carrying out the test.